FIGURE 7. The Parallax Say It Module,
a complete voice recognition system on
one board. This module is similar to the
VRBot and EasyVR products from
VeeAR (all are made by the same
company). Photo courtesy Parallax, Inc.

Sound In,
Sound Out

Sound isn’t a one-way street. In
this article, we looked at ways to
control a robot with sound, but you
can also have your robot
produce sound — and music
and even voice effects. I’ve
saved these topics for the next
time, where you’ll learn how to
make your Arduino-based robot
sound off. You’ll discover ways
to produce basic sound effects,
play recorded or electronic
music, and speak in a classic
robotic voice. SV

FIGURE 8. Wiring diagram for
the Say It Module to the

Arduino. The LED connection is
optional, but recommended.

Laser Range
Finder

Designed in conjunction with Grand Idea Studio, the
Parallax Laser Range Finder (LRF) Module (#28044;
$129.99) is a distance-measuring instrument that uses
laser technology to calculate the distance to a targeted
object. The design uses a Propeller processor, CMOS
camera, and laser diode. Distance to a targeted object is
calculated by optical triangulation using simple trigonometry
between the centroid of laser light, camera, and object.